'''Lettuce''' (''Lactuca sativa'') is an annual plant
of the daisy family, Asteraceae
. It is most often grown as a leaf vegetable
, but sometimes for its stem and seeds. Lettuce is most often used for salad
s, although it is also seen in other kinds of food, such as soups, sandwiches and wraps; it can also be grilled.
One variety, the '''' (), or celtuce|asparagus lettuce (celtuce)
, is grown for its stems, which are eaten either raw or cooked. In addition to its main use as a leafy green, it has also gathered religious and medicinal significance over centuries of human consumption. Europe and North America originally dominated the market for lettuce, but by the late 20th century the consumption of lettuce had spread throughout the world. World production of lettuce and chicory
for calendar year
2013 was 24.9 million tonnes
, over half of which came from China.
Lettuce was first cultivated by...